Dispensing seal for flexible container

ABSTRACT

A dispensing seal for use with a flexible container for pouring viscous fluids. The seal includes a seat member disposed about the dispensing opening of the container and a flexible sealing member. When the sealing member is in its seated position, it forms a region having a generally concave shape as viewed from the exterior of the container, i.e., a region depressed inward toward the interior of the container. In this configuration the sealing member seals off the dispensing opening, fitting snugly within the wall or walls defining the dispensing opening. The sealing member is movably mounted so as to enable it to move with respect to the container between the seated position for retaining said fluid in the container under the weight of the fluid when said container is inverted and an unseated position for dispensing the fluid. The sealing member is formed of a material stiff enough to maintain the generally concave shape when in the seated position under the weight of a full container of the viscous fluid, yet flexible enough for the region to be deformed across the mid or median plane out of said generally concave shape when the container is squeezed to initiate pouring of the viscous fluid. Squeezing the container when the container is in inverted position exerts sufficient pressure on the sealing member to flex it to its convexly bulging shape thereby breaking the seal and allowing the fluid contents to pour out.

BACKGROUND OF THE INVENTION

The present invention relates to containers for pourable viscous fluids such as motor oil and is more particularly directed to a form of closure or seal for the pouring spout of such containers.

Automotive motor oil is commonly sold in individual bottle-like containers formed of a flexible plastic material. Oil is added to the engine by pouring it directly from the container typically one quart at a time into the engine's oil fill tube. It is common to spill a bit of oil on the engine as the container is tipped to bring the pouring spout to the oil fill tube. The spilled oil is unsightly, can leave a messy residue on the engine, and can burn off of hot engine surfaces giving off an undesirable odor as it burns.

A common way of dealing with the spillage problem is to use a wide-mouth funnel to catch the initial spurt of oil as the container is tipped. Another approach especially adapted to the flexible plastic bottle-like container is to provide a closure over the pouring spout of the container that initially supports the weight of the oil as the container is tilted to bring its pouring spout into position over the oil fill tube, but that ruptures when the container is squeezed to let the oil pour out. Such an approach is taken for example in the following U.S. Pat. No. 4,696,328 of Rhodes, Jr.; U.S. Pat. No. 4,938,390 of Markva, U.S. Pat. No. 5,353,968 of Good, Jr., and U.S. Pat. No. 6,457,613 of Patterson. This type of prior-art approach may be subject to one or more of the following deficiencies. The ruptured closure may restrict the flow of oil to substantially less than that allowed by the full size of the dispensing opening. The pressure required to initiate the rupture of the closure may be sufficiently great as to cause the oil to spurt uncontrollably as the closure is ruptured or may be sufficiently little as to allow premature rupture of the closure for example while grasping the container to remove the cap. Once ruptured, the closure may cause the flow to be uneven and irregular. Pieces of the closure material may dislodge and be carried into the engine along with the oil.

SUMMARY OF THE INVENTION

The present invention provides a dispensing seal for use with a flexible container that is especially suited for pouring viscous fluids such as motor oil and that does not use a rupturable closure, and thus is not subject to the disadvantages mentioned above. Moreover, since the seal of the present invention is not rupturable, in at least one of its embodiments it may be resealable when only a portion of the contents of the flexible container is poured out. The seal is secured to the pouring spout or other dispensing opening of the container and retains the viscous fluid in the container as the container is first brought into inverted position for pouring. As with the rupturable-membrane seals, when the container cap is removed and container is inverted, it only takes a small squeeze to release the seal, allowing the fluid to flow freely from the container.

Briefly, a seal according to the invention includes a seat member disposed about the dispensing opening and a flexible sealing member. When the sealing member is in its seated position, it forms a region having a generally concave shape as viewed from the exterior of the container, i.e., a region depressed inward toward the interior of the container. In this configuration the sealing member seals off the dispensing opening, fitting snugly within the wall or walls defining the dispensing opening. The sealing member is movably mounted so as to enable it to move with respect to the container between the seated position for retaining said fluid in the container under the weight of the fluid when said container is inverted and an unseated position for dispensing the fluid. The sealing member is formed of a material stiff enough to maintain the generally concave shape when in the seated position under the weight of a full container of the viscous fluid, yet flexible enough for the region to be deformed across the mid or median plane out of said generally concave shape, into a more or less convex shape bulging across the median plane, when the container is squeezed to initiate pouring of the viscous fluid. Squeezing the container when the container is in inverted position exerts sufficient pressure on the sealing member to flex it to its convexly bulging shape thereby breaking the seal and allowing the fluid contents to pour out.

In one form of embodiment the seat for the seal may be formed directly on an interior wall defining the dispensing opening, and the sealing member may be connected to the interior wall. In another form of embodiment the seal mechanism is formed in a separate insert, which may then be inserted into the dispensing opening of the container.

The sealing member is connected to the container or insert through an intermediate connecting structure, and examples of forms of connecting structures are provided herein. In one form of embodiment the sealing member may be hinged to the container in a manner integrally formed with the container or insert.

It is an object of the invention to provide a closure that prevents premature release of the contents as the container is brought into inverted position for pouring and that opens smoothly when the fluid starts to pour. It is a further object to provide such a seal that achieves its effect without relying on a rupturable membrane.

It is another object of the invention to provide a seal that can be readily resealed when less than the full contents of the container is poured out.

Other aspects, advantages, and novel features of the invention are described below or will be readily apparent to those skilled in the art from the following specifications and drawings of illustrative embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an overall perspective view showing a bottle with an embodiment of seal according to the invention.

FIG. 2 is a cross-sectional view of the seal in the embodiment of FIG. 1 shown in seated position in the bottle.

FIG. 3 is a cross-sectional view of an alternative embodiment of seal shown in seated position in a bottle.

FIG. 3A is an overall view of the seal member in FIG. 3.

FIG. 4 is an overall view of a sealing member hinged to the container.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

FIG. 1 shows a flexible container 10 that holds a pourable viscous fluid such as automotive motor oil. Container 10 is made of a flexible plastic material that has sufficient give that it deforms slightly when squeezed. Such containers are commonplace for use with motor oils and other substances. The container has a dispensing opening 11 through which the oil is poured, and the opening is covered by a sealing member 12, which is movable between a dispensing position (seen in FIG. 1) and a seated position (seen in FIG. 2). The container is shown in FIG. 1 in inverted position with its viscous contents, indicated generally at reference numeral 13, pouring past the sealing member. As the container is brought to its inverted position, the seated sealing member 12 retains the viscous fluid in the container so that the fluid will not drip or spurt out. When the container is in position over the intended receptacle, the user gently squeezes the container causing sealing member 12 to be released and allow the viscous fluid to flow. The dispensing seal disclosed herein provides for improved retention of the viscous fluid as the container is brought to its inverted position and improved pouring of the viscous fluid once the container is squeezed. In addition, it is resealable.

The structure and operation of the dispensing seal will now be described by reference to the cross-sectional view of FIG. 2. The cross section of the wall of the container that defines the dispensing opening is shown at 16. The upper portion of wall 16 is formed in conventional manner with exterior threads 17 for screwing on a cap. The interior of wall 16 is formed with a small annular rim 18 proximate the top of the dispensing opening that serves as a seat for sealing member 12. The sealing member is formed of a flexible, yet somewhat stiff material. A range of different sealing member materials may be used as will be appreciated from the discussion below. When the sealing member is seated on annular rim 18, it has a depressed region 19 forming a generally concave shape. The sealing member is flexible, yet stiff enough to hold this generally concave shape. Concave here means that the sealing member is deformed to extend inward into the dispensing opening. That is, the sealing member in its seated configuration looks concave as viewed from the outside of the container. The shape is referred to herein as generally concave to allow for minor variations from strict concavity due to such factors as minor imperfections in the material of the sealing member or minor structural features such as ribbing or decorative patterns that may be included on the sealing member and that might depart from strict concavity.

The sealing member is attached to the container generally through an intermediate connection. In the embodiment of FIGS. 1 and 2 the sealing member is attached to the container by a movable plunger support bracket formed of a plunger guide 21 attached to a side of the container wall 16 by web 22. The guide 21 defines an elongate bore 23 through which a plunger 24 slides. Plunger 24 is provided with a stop 25 at its inner end and a stop 26 at its outer end. The stop 26 is secured to sealing member 12 at a generally central position as shown in FIG. 2. The sealing member and stop 26 may be secured to one another by any appropriate means, for example, with an adhesive or by heat welding. For ease of assembly stop 25 in the illustrated embodiment has a split conical shape. During assembly the plunger with sealing member pre-attached is inserted through bore 23, and the split conical end squeezes through the bore and expands to provide the stopping action.

In operation, the seal works as follows. In the normal state the sealing member is in its concave configuration seated on seating ring 18 as shown in FIG. 2. When the cap is removed and as container 10 is inverted, its fluid contents impinges upon sealing member 12, and the weight of the fluid presses on the inward-facing convex side of the sealing member tending to flatten out the sealing member. As the sealing member starts to flatten, the sealing member is caused to spread slightly in the radial direction. The periphery of the sealing member in its seated configuration, however, fits snugly within the dispensing opening, generally engaging the container wall, and thus is urged into greater engagement with the container wall as the sealing member flattens out, thereby causing the sealing member to be squeezed more tightly in the dispensing opening. Thus, a small force tending to flatten out the sealing member will have the initial net result of making the sealing member fit more tightly in the dispensing opening, and this retains the fluid in the container against its own weight even when the cap is removed. If the user should inadvertently squeeze the bottle slightly in the process of inverting it, the increased pressure on the sealing member caused by the squeezing action will in fact help tighten the seal. When the bottle is in inverted position and the user is ready to release the contents, the user applies a greater squeeze, thereby exerting sufficient pressure on the (now inverted) sealing member, pushing it through its median plane (that is, the plane of rim 18) so that it starts to bulge slightly in the opposite direction; that is, the sealing member is deformed through the median plane out of the initial generally concave shape to become more or less concave in the opposite direction. This has the effect of releasing the sealing member and allowing the fluid contents of the container to pour out. When the container is brought into upright position again, the plunger slides back in bore 23 and sealing member 12 falls back onto rim 18. The flexible sealing member can then be pushed into its concave sealing configuration on the rim to reseal the container. For example, the user can simply push on the sealing member slightly to urge it past the median plane back into its seated concave configuration to reseal the container. The cap for the container may also be formed with a central projection on its inside that is sized and positioned so that when the cap is screwed onto the container, the central projection presses against the sealing member and maintains it in its generally concave sealing configuration. This ensures that when the cap is screwed on, no amount of squeezing or shaking of the container will inadvertently cause the sealing member to flex in the opposite direction and break seal. Moreover, if the material of the sealing member is able to hold its generally concave sealing shape on its own and is sufficiently resilient, the sealing member will automatically return to its generally concave shape and come to rest in the seated position on the rim already in its starting concave shape ready for sealing.

It may now be appreciated that the sealing member requires the right combination of size and flexibility/stiffness of the material to function properly. It must be sized so that it fits snugly within the dispensing opening when it is in its concave sealing configuration seated on the rim. That means that when the sealing member is flat, it will be dimensioned slightly larger than the dispensing opening, even if only minutely so. Thus, for a circular dispensing opening and circular sealing member, the sealing member, when flat, will have a diameter slightly greater than the inside diameter of wall 16 defining the dispensing opening. The difference in diameters may be only slight, and in some cases barely noticeable, but it must be sufficient that the sealing member in its concave sealing configuration fit snugly in the dispensing opening so that the seal will become tighter as the sealing member flattens out. The seal is formed primarily by frictional engagement of the peripheral edges of the sealing member against the container wall. The friction of this engagement is increased when pressure is applied to the sealing member in its starting concave seated configuration, thereby making a tighter seal. The radial force exerted by the sealing member against the container wall then diminishes as the sealing member bulges in the opposite direction until the seal is finally released. The sealing member can be formed of any material having sufficient flexibility and stiffness and, if desired, resilience, to behave as just described.

In one embodiment the sealing member has no significant resilience so that it does not snap back automatically to its original concave configuration when the pressure is removed. In this embodiment if it is desired to reseal the container, it will generally be necessary to apply a force to the outside of the sealing member to push it back into its original concave configuration, for example, by pressing on the sealing member with the user's finger or with a projection within the container cap as mentioned above. This embodiment of sealing member will suffice for most applications and may be preferable if more economical to manufacture. In another embodiment it is desirable that the sealing member return automatically to its initial concave shape when the force on it is removed. In this embodiment the sealing member behaves like the bottom of an oil can. When a user presses on the bottom of an oil can, the bottom of the can snaps in slightly and then automatically snaps back out when the force is removed. A sealing member behaving such as this may be desirable because the member is returned automatically to its sealing configuration, ready to reseal the container. This is plainly desirable where it is expected that not all of the contents of the container will be poured out at one time.

In general, the material used for the sealing member may be a lower-durometer plastic material, although in an embodiment having a sufficiently thin sealing member a high-density polyethylene material or equivalent may be used. In any case the correct combination of flexibility, stiffness and resilience depends to some extent on the size and shape of dispensing opening that is to be sealed and the weight of the fluid to be held in the container as the container is inverted. The combination of flexibility, stiffness and possibly resilience, as well as the proper diameter of the sealing member (or other transverse dimensions of the sealing member for non-circular configurations) are best determined empirically for any given embodiment and may be readily determined by the routine practitioner in the art. The defining criteria are whether the sealing member is stiff enough to hold its concave sealing shape when seated on the rim at least under the weight of the intended contents of the container, and whether the sealing member is flexible enough to be pushed through its median plane to start to bulge in the opposite direction when the container is given a squeeze of a magnitude normally exerted for intentionally releasing the contents of the container.

It should now be apparent that seating rim 18 serves primarily as a positioning stop for sealing member 12. It holds the sealing member in place and provides a lip for the sealing member to push against to form the concave shape. For this function it is not necessary that the seating rim be continuous as illustrated in the figures, but may comprise a plurality of stop segments positioned about the periphery of the sealing member.

An alternative embodiment of dispensing seal is shown in FIGS. 3 and 3A. FIG. 3A shows a sealing member 32 with a concave central region 33 in the manner of sealing member 12 of FIG. 2. The sealing member may be preformed with a concave region, or it may be formed flat at time of manufacture and take its concave shape only when properly seated in the dispensing opening. The sealing member 32, however, is provided with a different means of securement to the container. Sealing member 32 is formed with a split detented tab 34 that extends generally perpendicular to the plane of sealing member 32. Tab 34 is inserted into a slot, indicated at reference numeral 35 in FIG. 3 and is held in the slot by projecting detents 36. The connection between sealing member 32 and tab 34 is flexible enough that the sealing member can rotate about the line of connection. In general, the sealing member and tab may be formed of the same material, and the tab 34 may be made narrow enough to provide the appropriate flexibility.

FIG. 3 shows another aspect of the invention especially suitable for retrofitting separately manufactured containers. In FIG. 3 a separate insert 38 is provided for holding the sealing member. Insert 38 has a short, generally cylindrical shape with a seating ring 39 for receiving the sealing member. The sealing member is secured to the insert instead of directly to the inside of the container. The insert is then slid into the top of the container. In the embodiment of FIG. 3 the insert is held in the top of the container by an annular friction ridge 41 although other means of securement may also be used such as adhesives or press fitting. In the embodiment of FIG. 3 insert 38 is provided with an annular positioning stop 42 at its top rim for positioning the insert flush with the top of the container. Although the annular stop 42 provides a neater appearance and makes it easier to position the insert, its use is not necessary.

FIG. 4 shows another embodiment, in which the sealing member 47 is formed integrally with the container or insert. Wall 48 is the outer wall of the container or of the insert. A seating rim 49 is partially visible. Sealing member 47 is hinged to wall 48 at the top of the wall by a connecting plastic hinge 50. The sealing member 47, hinge 50, wall 48 and generally rim 49 are integrally formed of the same material.

The above descriptions and drawings are given to illustrate and provide examples of various aspects of the invention in various embodiments. It is not intended to limit the invention only to these examples and illustrations. Given the benefit of the above disclosure, those skilled in the art may be able to devise various modifications and alternate constructions that although differing from the examples disclosed herein nevertheless enjoy the benefits of the invention and fall within the scope of the invention, which is to be defined by the following claims. Any limitation in the claims not expressly using the word “means” is not intended to be interpreted as a “means plus function” limitation in accordance with Title 35, United States Code, Section 112, and any claim limitation expressly using the word “means” is intended to be so interpreted. 

1. A dispensing seal for use in combination with a flexible container for a pourable viscous fluid, the container having a dispensing opening for pouring the fluid from the container, comprising: a seat member disposed about said dispensing opening, said seat member defining a median plane; and a sealing member having a seated position on said seat member, said sealing member having a region forming a generally concave shape when in said seated configuration; wherein said sealing member is movably mounted so as to enable movement of said sealing member with respect to said container between said seated position for retaining said fluid in said container under the weight of said fluid when said container is inverted and an unseated position for dispensing said fluid; wherein said sealing member is shaped and sized to fit snugly within said dispensing opening when in said seated position; and wherein said sealing member is formed of a material stiff enough to maintain said generally concave shape when in said seated position under the weight of a full container of said pourable viscous fluid and flexible enough for said region to be deformed across said median plane out of said generally concave shape when the container is squeezed to initiate pouring of said viscous fluid.
 2. The dispensing seal of claim 1, further comprising: a plunger fixed at a first end to said sealing member; and a plunger support bracket mounted in said dispensing opening and having a bore for receiving said plunger; wherein said plunger extends through said bore and is sized to slide in said bore to permit said sealing member to travel between said seated and unseated positions.
 3. The dispensing seal of claim 1 wherein said sealing member is formed with a tab hingedly connected to said sealing member at the periphery of the sealing member, and a slot is defined at said dispensing opening receiving said tab for movably mounting said sealing member at said dispensing opening.
 4. The dispensing seal of claim 3 wherein said slot is defined in said seat member.
 5. The dispensing seal of claim 1 wherein said sealing member is hingedly connected directly to a wall defining said dispensing opening.
 6. The dispensing seal of claim 5 wherein said wall defining said dispensing opening, said sealing member, and said seat member are integrally formed together.
 7. An insert providing a dispensing seal for use in combination with a flexible container for a pourable viscous fluid, the container having a dispensing opening for pouring the fluid from the container, comprising: an insert wall sized and shaped to mount within said dispensing opening; a seat member disposed in said insert about said insert wall, said seat member defining a median plane; and a sealing member having a seated position on said seat member, said sealing member having a region forming a generally concave shape when in said seated configuration; wherein said sealing member is movably mounted so as to enable said sealing member to move with respect to said insert wall between said seated position for retaining said fluid in said container under the weight of said fluid when said container is inverted and an unseated position for dispensing said fluid; wherein said sealing member is shaped and sized to fit snugly within said insert wall when in said seated position; and wherein said sealing member is formed of a material stiff enough to maintain said generally concave shape when in said seated position under the weight of a full container of said pourable viscous fluid and flexible enough for said region to be deformed across said median plane out of said generally concave shape when the container is squeezed to initiate pouring of said viscous fluid.
 8. The insert of claim 7, further comprising: a plunger fixed at a first end to said sealing member; and a plunger support bracket mounted in said dispensing opening and having a bore for receiving said plunger; wherein said plunger extends through said bore and is sized to slide in said bore to permit said sealing member to travel between said seated and unseated positions.
 9. The insert of claim 7 wherein said sealing member is formed with a tab hingedly connected to said sealing member at the periphery of the sealing member, and a slot is defined at said insert wall receiving said tab for movably mounting said sealing member to said insert wall.
 10. The dispensing seal of claim 9 wherein said slot is defined in said seat member.
 11. The dispensing seal of claim 7 wherein said insert wall, said sealing member, and said seat member are integrally formed together. 